title: Influence of manual therapy on functional mobility after joint injury in a rat model.
abstract: BACKGROUND
  Animal models can be used to investigate manual therapy mechanisms, but testing manipulation in animal models is problematic because animals cannot directly report their pain.
  
  
  OBJECTIVE
  To develop a rat model of inflammatory joint injury to test the efficacy of manual therapy in reducing nociception and restoring function.
  
  
  METHODS
  The authors induced acute inflammatory joint injury in rats by injecting carrageenan into the ankle and then measured voluntary running wheel activity in treated and untreated rats. Treatments included manual therapy applied to the ankle and knee of the injured limb and several analgesic medications (eg, morphine, ketorolac, prednisone).
  
  
  RESULTS
  Intra-articular injection of carrageenan to the ankle produced significant swelling (diameter of the ankle increased by 64% after injection; P=.004) and a robust reduction in voluntary running wheel activity (running distance reduced by 91% compared with controls; P<.001). Injured rats gradually returned to running levels equal to controls over 10 days. Neither manual therapy nor analgesic medications increased running wheel activity relative to untreated rats.
  
  
  CONCLUSIONS
  Voluntary running wheel activity appears to be an appropriate functional measure to evaluate the impact of an acute inflammatory joint injury. However, efforts to treat the injury did not restore running relative to untreated rats.
authors.affiliation: A.T. Still Research Institute, A.T. Still University-Kirksville College of Osteopathic Medicine, 800 W Jefferson St, Kirksville, MO 63501-1443. rruhlen@atsu.edu.
authors.forename: Rachel L
authors.initials: RL
authors.lastname: Ruhlen
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Snider
authors.forename: Neil J
authors.initials: NJ
authors.lastname: Sargentini
authors.forename: Bart D
authors.initials: BD
authors.lastname: Worthington
authors.forename: Vineet K
authors.initials: VK
authors.lastname: Singh
authors.forename: Vanessa K
authors.initials: VK
authors.lastname: Pazdernik
authors.forename: Jane C
authors.initials: JC
authors.lastname: Johnson
authors.forename: Brian F
authors.initials: BF
authors.lastname: Degenhardt
mesh_terms: D000208:Acute Disease; D000818:Animals; D016512:Ankle Injuries / Q000503:physiopathology / Q000628:therapy*; D000843:Ankle Joint / Q000503:physiopathology*; D004195:Disease Models, Animal; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D026201:Musculoskeletal Manipulations / Q000379:methods*; D005082:Physical Exertion / Q000502:physiology*; D016059:Range of Motion, Articular; D051381:Rats; D016896:Treatment Outcome